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    <title>Document</title>
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        .pop{
            width: 100px;
            height: 100px;
            background-color: rebeccapurple;
        }
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<body>
    <div class="pop">
        <a href="javacsript:;">1</a>
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          a.addEventListener('click',function(){
            a.parentNode.style='width:200px;background:red;'
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